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Montana Field Guide

Montana Field Guides

Oregon Checker-mallow - Sidalcea oregana

Species of Concern

Global Rank: G5
State Rank: S2S3
* (see State Rank Reason below)

Agency Status
USFWS:
USFS:
BLM:
MNPS Threat Rank: 1
C-value: 3

External Links






State Rank Reason (see State Rank above)
Known from two widely separate sites in Gallatin and Lake counties. Habitats occupied by the species are susceptible to weed invasion and both locations have a large component of weedy species. However, S. oregana appears capable of tolerating at least some competition from these weedy species. The Lake County population occurs near and along Highway 93 and has the potential to be significantly negatively impacted by highway construction.
  • Details on Status Ranking and Review
    Oregon Checker-mallow (Sidalcea oregana) Conservation Status Review
    Review Date = 05/30/2012
    View State Conservation Rank Criteria
    Population Size

    Score1-2 - Small to Moderate. Population size is imprecisely known but is believed to be >2,000 individuals and <100,000 individuals.

    Range Extent

    Score1 - Peripheral, Disjunct or Sporadic Distribution in MT: Widespread species that is peripheral, disjunct or sporadically distributed within MT such that it occurs in <5% of the state (<7,500 sq. miles or the combined area of Beaverhead and Ravalli Counties) or is restricted to 4-5 sub-basins.

    Area of Occupancy

    Score3 - Very Low: Generally occurring in 3 or fewer Subwatersheds (6th Code HUC’s).

    Environmental Specificity

    Score1 - Moderate: Species is restricted to a specific habitat that is more widely distributed or to several restricted habitats and is typically dependent upon relatively unaltered, good-quality habitat (C Values of 5-7).

    CommentAppears to be tolerant of some level of disturbance.

    Trends

    Score1-3 - Declining: Species is likely declining though the magnitude of declines is uncertain. Declines may be based upon range extent and/or occupied area in the recent past (approximately 30 years).

    CommentTrends are unknown, though may be declining due to impacts to habitat quality. Road construction and invasive species may have detrimentally impacted the populations.

    Threats

    Score2-3 - High to Very High.

    Intrinsic Vulnerability

    Score0-1 - Low to Moderate Vulnerability.

    Raw Conservation Status Score

    Score 9 to 14 total points scored out of a possible 19.

 
General Description
Oregon Checker-mallow is an herbaceous perennial with erect stems that are 2-15 dm tall and arising from a branched rootcrown that surmounts a taproot. The basal leaves have long petioles and round blades that are deeply palmately divided into 5-9 nearly linear lobes. The alternate stem leaves become smaller with few lobes upward. The lower stems and leaves are sparsely covered with star-shaped hairs. Short-stalked flowers are borne in a terminal spike. Some flowers are bisexual, while in others, the anthers are sterile or lacking. Each pink flower has a 5-lobed, hairy calyx that is 4-9 mm long and 5 separate, oblong, shallowly bilobed petals that are 15-20 mm long. Numerous stamens are united into a tube surrounding the style. The numerous stigmas are linear. The fruit, which is 2-3 mm long, is a flattened-globose capsule with many sections, giving it the appearance of a peeled orange.

Phenology
Flowering in the end of June-mid-August, fruiting in late August.

Diagnostic Characteristics
Iliamna rivularis has leaves with broader lobes and globose stigmas.

Species Range
Present
 


Range Comments
B.C. to CA, east to MT, WY, and UT. Peripheral.

Summary of Observations Submitted for Montana
Number of Observations: 18

(Click on the following maps and charts to see full sized version) Map Help and Descriptions
Relative Density

Recency

 

(Observations spanning multiple months or years are excluded from time charts)



Habitat
Grasslands in the valley and montane zones.

Ecological Systems Associated with this Species

References
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Citation for data on this website:
Oregon Checker-mallow — Sidalcea oregana.  Montana Field Guide.  .  Retrieved on , from